12 |
use Carp; |
use Carp; |
13 |
use Data::Dumper; |
use Data::Dumper; |
14 |
|
|
15 |
|
our $VERSION = '0.07'; |
16 |
|
|
17 |
our $VERSION = '0.03'; |
# block size for this filesystem |
18 |
|
use constant BLOCK => 1024; |
19 |
|
|
20 |
=head1 NAME |
=head1 NAME |
21 |
|
|
26 |
use Fuse::DBI; |
use Fuse::DBI; |
27 |
Fuse::DBI->mount( ... ); |
Fuse::DBI->mount( ... ); |
28 |
|
|
29 |
See L<run> below for examples how to set parametars. |
See C<run> below for examples how to set parameters. |
30 |
|
|
31 |
=head1 DESCRIPTION |
=head1 DESCRIPTION |
32 |
|
|
33 |
This module will use L<Fuse> module, part of C<FUSE (Filesystem in USErspace)> |
This module will use C<Fuse> module, part of C<FUSE (Filesystem in USErspace)> |
34 |
available at L<http://sourceforge.net/projects/avf> to mount |
available at L<http://fuse.sourceforge.net/> to mount |
35 |
your database as file system. |
your database as file system. |
36 |
|
|
37 |
That will give you posibility to use normal file-system tools (cat, grep, vi) |
That will give you possibility to use normal file-system tools (cat, grep, vi) |
38 |
to manipulate data in database. |
to manipulate data in database. |
39 |
|
|
40 |
It's actually opposite of Oracle's intention to put everything into database. |
It's actually opposite of Oracle's intention to put everything into database. |
48 |
|
|
49 |
Mount your database as filesystem. |
Mount your database as filesystem. |
50 |
|
|
51 |
|
Let's suppose that your database have table C<files> with following structure: |
52 |
|
|
53 |
|
id: int |
54 |
|
filename: text |
55 |
|
size: int |
56 |
|
content: text |
57 |
|
writable: boolean |
58 |
|
|
59 |
|
Following is example how to mount table like that to C</mnt>: |
60 |
|
|
61 |
my $mnt = Fuse::DBI->mount({ |
my $mnt = Fuse::DBI->mount({ |
62 |
filenames => 'select name from files_table as filenames', |
'filenames' => 'select id,filename,size,writable from files', |
63 |
read => 'sql read', |
'read' => 'select content from files where id = ?', |
64 |
update => 'sql update', |
'update' => 'update files set content = ? where id = ?', |
65 |
dsn => 'DBI:Pg:dbname=webgui', |
'dsn' => 'DBI:Pg:dbname=test_db', |
66 |
user => 'database_user', |
'user' => 'database_user', |
67 |
password => 'database_password' |
'password' => 'database_password', |
68 |
|
'invalidate' => sub { ... }, |
69 |
}); |
}); |
70 |
|
|
71 |
|
Options: |
72 |
|
|
73 |
|
=over 5 |
74 |
|
|
75 |
|
=item filenames |
76 |
|
|
77 |
|
SQL query which returns C<id> (unique id for that row), C<filename>, |
78 |
|
C<size> and C<writable> boolean flag. |
79 |
|
|
80 |
|
=item read |
81 |
|
|
82 |
|
SQL query which returns only one column with content of file and has |
83 |
|
placeholder C<?> for C<id>. |
84 |
|
|
85 |
|
=item update |
86 |
|
|
87 |
|
SQL query with two pace-holders, one for new content and one for C<id>. |
88 |
|
|
89 |
|
=item dsn |
90 |
|
|
91 |
|
C<DBI> dsn to connect to (contains database driver and name of database). |
92 |
|
|
93 |
|
=item user |
94 |
|
|
95 |
|
User with which to connect to database |
96 |
|
|
97 |
|
=item password |
98 |
|
|
99 |
|
Password for connecting to database |
100 |
|
|
101 |
|
=item invalidate |
102 |
|
|
103 |
|
Optional anonymous code reference which will be executed when data is updated in |
104 |
|
database. It can be used as hook to delete cache (for example on-disk-cache) |
105 |
|
which is created from data edited through C<Fuse::DBI>. |
106 |
|
|
107 |
|
=item fork |
108 |
|
|
109 |
|
Optional flag which forks after mount so that executing script will continue |
110 |
|
running. Implementation is experimental. |
111 |
|
|
112 |
|
=back |
113 |
|
|
114 |
=cut |
=cut |
115 |
|
|
116 |
my $dbh; |
my $dbh; |
120 |
sub read_filenames; |
sub read_filenames; |
121 |
sub fuse_module_loaded; |
sub fuse_module_loaded; |
122 |
|
|
123 |
|
# evil, evil way to solve this. It makes this module non-reentrant. But, since |
124 |
|
# fuse calls another copy of this script for each mount anyway, this shouldn't |
125 |
|
# be a problem. |
126 |
|
my $fuse_self; |
127 |
|
|
128 |
sub mount { |
sub mount { |
129 |
my $class = shift; |
my $class = shift; |
130 |
my $self = {}; |
my $self = {}; |
134 |
|
|
135 |
print Dumper($arg); |
print Dumper($arg); |
136 |
|
|
137 |
|
unless ($self->fuse_module_loaded) { |
138 |
|
print STDERR "no fuse module loaded. Trying sudo modprobe fuse!\n"; |
139 |
|
system "sudo modprobe fuse" || die "can't modprobe fuse using sudo!\n"; |
140 |
|
} |
141 |
|
|
142 |
carp "mount needs 'dsn' to connect to (e.g. dsn => 'DBI:Pg:dbname=test')" unless ($arg->{'dsn'}); |
carp "mount needs 'dsn' to connect to (e.g. dsn => 'DBI:Pg:dbname=test')" unless ($arg->{'dsn'}); |
143 |
carp "mount needs 'mount' as mountpoint" unless ($arg->{'mount'}); |
carp "mount needs 'mount' as mountpoint" unless ($arg->{'mount'}); |
144 |
|
|
145 |
# save (some) arguments in self |
# save (some) arguments in self |
146 |
$self->{$_} = $arg->{$_} foreach (qw(mount)); |
foreach (qw(mount invalidate)) { |
147 |
|
$self->{$_} = $arg->{$_}; |
148 |
|
} |
149 |
|
|
150 |
foreach (qw(filenames read update)) { |
foreach (qw(filenames read update)) { |
151 |
carp "mount needs '$_' SQL" unless ($arg->{$_}); |
carp "mount needs '$_' SQL" unless ($arg->{$_}); |
153 |
|
|
154 |
$ctime_start = time(); |
$ctime_start = time(); |
155 |
|
|
156 |
|
my $pid; |
157 |
if ($arg->{'fork'}) { |
if ($arg->{'fork'}) { |
158 |
my $pid = fork(); |
$pid = fork(); |
159 |
die "fork() failed: $!" unless defined $pid; |
die "fork() failed: $!" unless defined $pid; |
160 |
# child will return to caller |
# child will return to caller |
161 |
if ($pid) { |
if ($pid) { |
162 |
$self ? return $self : return undef; |
my $counter = 4; |
163 |
|
while ($counter && ! $self->is_mounted) { |
164 |
|
select(undef, undef, undef, 0.5); |
165 |
|
$counter--; |
166 |
|
} |
167 |
|
if ($self->is_mounted) { |
168 |
|
return $self; |
169 |
|
} else { |
170 |
|
return undef; |
171 |
|
} |
172 |
} |
} |
173 |
} |
} |
174 |
|
|
175 |
$dbh = DBI->connect($arg->{'dsn'},$arg->{'user'},$arg->{'password'}, {AutoCommit => 0, RaiseError => 1}) || die $DBI::errstr; |
$dbh = DBI->connect($arg->{'dsn'},$arg->{'user'},$arg->{'password'}, {AutoCommit => 0, RaiseError => 1}) || die $DBI::errstr; |
176 |
|
|
177 |
$sth->{filenames} = $dbh->prepare($arg->{'filenames'}) || die $dbh->errstr(); |
$sth->{'filenames'} = $dbh->prepare($arg->{'filenames'}) || die $dbh->errstr(); |
178 |
|
|
179 |
$sth->{'read'} = $dbh->prepare($arg->{'read'}) || die $dbh->errstr(); |
$sth->{'read'} = $dbh->prepare($arg->{'read'}) || die $dbh->errstr(); |
180 |
$sth->{'update'} = $dbh->prepare($arg->{'update'}) || die $dbh->errstr(); |
$sth->{'update'} = $dbh->prepare($arg->{'update'}) || die $dbh->errstr(); |
181 |
|
|
182 |
|
|
183 |
|
$self->{'sth'} = $sth; |
184 |
|
|
185 |
|
$self->{'read_filenames'} = sub { $self->read_filenames }; |
186 |
$self->read_filenames; |
$self->read_filenames; |
187 |
|
|
188 |
my $mount = Fuse::main( |
$fuse_self = \$self; |
189 |
|
|
190 |
|
Fuse::main( |
191 |
mountpoint=>$arg->{'mount'}, |
mountpoint=>$arg->{'mount'}, |
192 |
getattr=>\&e_getattr, |
getattr=>\&e_getattr, |
193 |
getdir=>\&e_getdir, |
getdir=>\&e_getdir, |
198 |
utime=>\&e_utime, |
utime=>\&e_utime, |
199 |
truncate=>\&e_truncate, |
truncate=>\&e_truncate, |
200 |
unlink=>\&e_unlink, |
unlink=>\&e_unlink, |
201 |
|
rmdir=>\&e_unlink, |
202 |
debug=>0, |
debug=>0, |
203 |
); |
); |
204 |
|
|
205 |
|
exit(0) if ($arg->{'fork'}); |
206 |
|
|
207 |
|
return 1; |
208 |
|
|
|
if (! $mount) { |
|
|
warn "mount on ",$arg->{'mount'}," failed!\n"; |
|
|
return undef; |
|
|
} |
|
209 |
}; |
}; |
210 |
|
|
211 |
|
=head2 is_mounted |
212 |
|
|
213 |
|
Check if fuse filesystem is mounted |
214 |
|
|
215 |
|
if ($mnt->is_mounted) { ... } |
216 |
|
|
217 |
|
=cut |
218 |
|
|
219 |
|
sub is_mounted { |
220 |
|
my $self = shift; |
221 |
|
|
222 |
|
my $mounted = 0; |
223 |
|
my $mount = $self->{'mount'} || confess "can't find mount point!"; |
224 |
|
if (open(MTAB, "/etc/mtab")) { |
225 |
|
while(<MTAB>) { |
226 |
|
$mounted = 1 if (/ $mount fuse /i); |
227 |
|
} |
228 |
|
close(MTAB); |
229 |
|
} else { |
230 |
|
warn "can't open /etc/mtab: $!"; |
231 |
|
} |
232 |
|
|
233 |
|
return $mounted; |
234 |
|
} |
235 |
|
|
236 |
|
|
237 |
=head2 umount |
=head2 umount |
238 |
|
|
239 |
Unmount your database as filesystem. |
Unmount your database as filesystem. |
248 |
sub umount { |
sub umount { |
249 |
my $self = shift; |
my $self = shift; |
250 |
|
|
251 |
system "fusermount -u ".$self->{'mount'} || croak "umount error: $!"; |
if ($self->{'mount'} && $self->is_mounted) { |
252 |
|
system "( fusermount -u ".$self->{'mount'}." 2>&1 ) >/dev/null" || |
253 |
|
system "sudo umount ".$self->{'mount'} || |
254 |
|
return 0; |
255 |
|
return 1; |
256 |
|
} |
257 |
|
|
258 |
return 1; |
return 0; |
259 |
|
} |
260 |
|
|
261 |
|
$SIG{'INT'} = sub { |
262 |
|
if ($fuse_self && $$fuse_self->umount) { |
263 |
|
print STDERR "umount called by SIG INT\n"; |
264 |
|
} |
265 |
|
}; |
266 |
|
|
267 |
|
$SIG{'QUIT'} = sub { |
268 |
|
if ($fuse_self && $$fuse_self->umount) { |
269 |
|
print STDERR "umount called by SIG QUIT\n"; |
270 |
|
} |
271 |
|
}; |
272 |
|
|
273 |
|
sub DESTROY { |
274 |
|
my $self = shift; |
275 |
|
if ($self->umount) { |
276 |
|
print STDERR "umount called by DESTROY\n"; |
277 |
|
} |
278 |
} |
} |
279 |
|
|
280 |
=head2 fuse_module_loaded |
=head2 fuse_module_loaded |
284 |
die "no fuse module loaded in kernel" |
die "no fuse module loaded in kernel" |
285 |
unless (Fuse::DBI::fuse_module_loaded); |
unless (Fuse::DBI::fuse_module_loaded); |
286 |
|
|
287 |
This function in called by L<mount>, but might be useful alone also. |
This function in called by C<mount>, but might be useful alone also. |
288 |
|
|
289 |
=cut |
=cut |
290 |
|
|
299 |
} |
} |
300 |
|
|
301 |
my %files; |
my %files; |
|
my %dirs; |
|
302 |
|
|
303 |
sub read_filenames { |
sub read_filenames { |
304 |
my $self = shift; |
my $self = shift; |
305 |
|
|
306 |
|
my $sth = $self->{'sth'} || die "no sth argument"; |
307 |
|
|
308 |
# create empty filesystem |
# create empty filesystem |
309 |
(%files) = ( |
(%files) = ( |
310 |
'.' => { |
'.' => { |
311 |
type => 0040, |
type => 0040, |
312 |
mode => 0755, |
mode => 0755, |
313 |
}, |
}, |
314 |
|
'..' => { |
315 |
|
type => 0040, |
316 |
|
mode => 0755, |
317 |
|
}, |
318 |
# a => { |
# a => { |
319 |
# cont => "File 'a'.\n", |
# cont => "File 'a'.\n", |
320 |
# type => 0100, |
# type => 0100, |
338 |
# first, entry is assumed to be file |
# first, entry is assumed to be file |
339 |
if ($d) { |
if ($d) { |
340 |
$files{$d} = { |
$files{$d} = { |
|
size => $dirs{$d}++, |
|
341 |
mode => 0755, |
mode => 0755, |
342 |
type => 0040 |
type => 0040 |
343 |
}; |
}; |
355 |
} |
} |
356 |
} |
} |
357 |
|
|
358 |
print "found ",scalar(keys %files)-scalar(keys %dirs)," files, ",scalar(keys %dirs), " dirs\n"; |
print "found ",scalar(keys %files)," files\n"; |
359 |
} |
} |
360 |
|
|
361 |
|
|
371 |
$file =~ s,^/,,; |
$file =~ s,^/,,; |
372 |
$file = '.' unless length($file); |
$file = '.' unless length($file); |
373 |
return -ENOENT() unless exists($files{$file}); |
return -ENOENT() unless exists($files{$file}); |
374 |
my ($size) = $files{$file}{size} || 1; |
my ($size) = $files{$file}{size} || BLOCK; |
375 |
my ($dev, $ino, $rdev, $blocks, $gid, $uid, $nlink, $blksize) = (0,0,0,1,0,0,1,1024); |
my ($dev, $ino, $rdev, $blocks, $gid, $uid, $nlink, $blksize) = (0,0,0,int(($size+BLOCK-1)/BLOCK),0,0,1,BLOCK); |
376 |
my ($atime, $ctime, $mtime); |
my ($atime, $ctime, $mtime); |
377 |
$atime = $ctime = $mtime = $files{$file}{ctime} || $ctime_start; |
$atime = $ctime = $mtime = $files{$file}{ctime} || $ctime_start; |
378 |
|
|
380 |
|
|
381 |
# 2 possible types of return values: |
# 2 possible types of return values: |
382 |
#return -ENOENT(); # or any other error you care to |
#return -ENOENT(); # or any other error you care to |
383 |
#print(join(",",($dev,$ino,$modes,$nlink,$uid,$gid,$rdev,$size,$atime,$mtime,$ctime,$blksize,$blocks)),"\n"); |
print "getattr($file) ",join(",",($dev,$ino,$modes,$nlink,$uid,$gid,$rdev,$size,$atime,$mtime,$ctime,$blksize,$blocks)),"\n"; |
384 |
return ($dev,$ino,$modes,$nlink,$uid,$gid,$rdev,$size,$atime,$mtime,$ctime,$blksize,$blocks); |
return ($dev,$ino,$modes,$nlink,$uid,$gid,$rdev,$size,$atime,$mtime,$ctime,$blksize,$blocks); |
385 |
} |
} |
386 |
|
|
392 |
my %out; |
my %out; |
393 |
foreach my $f (sort keys %files) { |
foreach my $f (sort keys %files) { |
394 |
if ($dirname) { |
if ($dirname) { |
395 |
if ($f =~ s/^\E$dirname\Q\///) { |
if ($f =~ s/^\Q$dirname\E\///) { |
396 |
$out{$f}++ if ($f =~ /^[^\/]+$/); |
$out{$f}++ if ($f =~ /^[^\/]+$/); |
397 |
} |
} |
398 |
} else { |
} else { |
414 |
|
|
415 |
$sth->{'read'}->execute($id) || die $sth->{'read'}->errstr; |
$sth->{'read'}->execute($id) || die $sth->{'read'}->errstr; |
416 |
$files{$file}{cont} = $sth->{'read'}->fetchrow_array; |
$files{$file}{cont} = $sth->{'read'}->fetchrow_array; |
417 |
|
# I should modify ctime only if content in database changed |
418 |
|
#$files{$file}{ctime} = time() unless ($files{$file}{ctime}); |
419 |
print "file '$file' content [",length($files{$file}{cont})," bytes] read in cache\n"; |
print "file '$file' content [",length($files{$file}{cont})," bytes] read in cache\n"; |
420 |
} |
} |
421 |
|
|
461 |
print "invalidate all cached content\n"; |
print "invalidate all cached content\n"; |
462 |
foreach my $f (keys %files) { |
foreach my $f (keys %files) { |
463 |
delete $files{$f}{cont}; |
delete $files{$f}{cont}; |
464 |
|
delete $files{$f}{ctime}; |
465 |
} |
} |
466 |
print "begin new transaction\n"; |
print "begin new transaction\n"; |
467 |
#$dbh->begin_work || die $dbh->errstr; |
#$dbh->begin_work || die $dbh->errstr; |
489 |
return 0; |
return 0; |
490 |
} |
} |
491 |
print "updated '$file' [",$files{$file}{id},"]\n"; |
print "updated '$file' [",$files{$file}{id},"]\n"; |
492 |
|
|
493 |
|
$$fuse_self->{'invalidate'}->() if (ref $$fuse_self->{'invalidate'}); |
494 |
} |
} |
495 |
return 1; |
return 1; |
496 |
} |
} |
545 |
return 0; |
return 0; |
546 |
} |
} |
547 |
|
|
548 |
sub e_statfs { return 255, 1, 1, 1, 1, 2 } |
sub e_statfs { |
549 |
|
|
550 |
sub e_unlink { |
my $size = 0; |
551 |
my $file = filename_fixup(shift); |
my $inodes = 0; |
552 |
|
|
553 |
return -ENOENT() unless exists($files{$file}); |
foreach my $f (keys %files) { |
554 |
|
if ($f !~ /(^|\/)\.\.?$/) { |
555 |
|
$size += $files{$f}{size} || 0; |
556 |
|
$inodes++; |
557 |
|
} |
558 |
|
print "$inodes: $f [$size]\n"; |
559 |
|
} |
560 |
|
|
561 |
print "unlink '$file' will invalidate cache\n"; |
$size = int(($size+BLOCK-1)/BLOCK); |
562 |
|
|
563 |
read_content($file,$files{$file}{id}); |
my @ret = (255, $inodes, 1, $size, $size-1, BLOCK); |
564 |
|
|
565 |
return 0; |
print "statfs: ",join(",",@ret),"\n"; |
566 |
|
|
567 |
|
return @ret; |
568 |
|
} |
569 |
|
|
570 |
|
sub e_unlink { |
571 |
|
my $file = filename_fixup(shift); |
572 |
|
|
573 |
|
# if (exists( $dirs{$file} )) { |
574 |
|
# print "unlink '$file' will re-read template names\n"; |
575 |
|
# print Dumper($fuse_self); |
576 |
|
# $$fuse_self->{'read_filenames'}->(); |
577 |
|
# return 0; |
578 |
|
if (exists( $files{$file} )) { |
579 |
|
print "unlink '$file' will invalidate cache\n"; |
580 |
|
read_content($file,$files{$file}{id}); |
581 |
|
return 0; |
582 |
|
} |
583 |
|
|
584 |
|
return -ENOENT(); |
585 |
} |
} |
586 |
1; |
1; |
587 |
__END__ |
__END__ |
590 |
|
|
591 |
Nothing. |
Nothing. |
592 |
|
|
593 |
|
=head1 BUGS |
594 |
|
|
595 |
|
Size information (C<ls -s>) is wrong. It's a problem in upstream Fuse module |
596 |
|
(for which I'm to blame lately), so when it gets fixes, C<Fuse::DBI> will |
597 |
|
automagically pick it up. |
598 |
|
|
599 |
=head1 SEE ALSO |
=head1 SEE ALSO |
600 |
|
|
601 |
C<FUSE (Filesystem in USErspace)> website |
C<FUSE (Filesystem in USErspace)> website |
602 |
L<http://sourceforge.net/projects/avf> |
L<http://fuse.sourceforge.net/> |
603 |
|
|
604 |
|
Example for WebGUI which comes with this distribution in |
605 |
|
directory C<examples/webgui.pl>. It also contains a lot of documentation |
606 |
|
about design of this module, usage and limitations. |
607 |
|
|
608 |
=head1 AUTHOR |
=head1 AUTHOR |
609 |
|
|